Every time I needed to "compress an image online" or "merge a PDF", I ended up on some site that makes you upload your file to their server. For a random meme, fine. For a contract, an ID scan, or anything private? No thanks.
So I built QuickKit — a growing kit of 38 free tools that run 100% in your browser. Your files and text never leave your device. No signup, no watermarks, no tracking of what you process.
How it works (the fun part)
The whole thing is a static site — no backend, no database, no server cost. Everything happens client-side with browser APIs:
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Image compressor / resizer → the Canvas API (
canvas.toBlob(type, quality)) - Image → PDF / Merge PDF → jsPDF and pdf-lib, entirely in-page
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Password / UUID generators → the Web Crypto API (
crypto.getRandomValues) for real cryptographic randomness - QR codes → generated locally, no redirect or tracking baked in
- Hash generator (SHA-256/1/512) → the SubtleCrypto API
- Countdown timer & "days since" counters → shareable via the URL itself (state encoded in query params), so there's still no backend
Because nothing is uploaded, the tools are faster and more private than upload-based services — and they even work offline once loaded (it's an installable PWA).
A few of the tools
Files & docs: image compressor, image resizer, image→PDF, merge PDF.
Dev utilities: JSON formatter, Base64, hash generator, UUID, timestamp converter, case converter.
Everyday: QR generator, word counter, unit/percentage/age calculators, world clock, "your life in weeks".
The privacy architecture, in one line
If the browser can do it, there's no reason to send the user's data to a server.
That principle killed all the usual costs (no servers, no storage, no compliance headaches) and made privacy the default instead of a feature.
Would love feedback — especially on tools you wish existed. What "online X converter" do you use that you wish ran locally?
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